1. Field of the Invention
The invention relates to a valve nozzle for introducing a flowable medium into a mixing chamber, which nozzle is provided with a delivery conduit with which at least one nozzle opening in a nozzle head is associated and which nozzle has an axially movable closure body, which is disposed on the outflow side of the nozzle opening and is supported on an actuating means that is connected to a closing spring and a driving means.
2. Description of the Related Art
Valve nozzles of this kind, as are needed for instance for fuel injection valves, are known for instance in the conception shown in German Patent Disclosure DE-A 19 33 489 with a closure body located on the inside, and in which nozzles there is a closure body disposed between the delivery conduit and the nozzle opening in the interior of the nozzle head, so that between the valve seat for the closure body on the one hand and the nozzle opening on the other, a relatively large residual chamber remains, with the result that such injection valves dribble after injection.
From European Patent Disclosure EP-A 0 599 168, a device for combined blow-injection of fuel and air is known, in which a plurality of nozzle openings for the delivery of fuel, which are closable via a central closure body, discharge into a mixing chamber formed by an air conduit. The air conduit in turn is likewise closable via a central, second closure body, which cooperates with the first closure body for the nozzle openings. Not only is the production cost high, but the two closure bodies also have a relatively large mass which, given the mass forces to be controlled, demands considerable actuation forces both for the closing spring and for the driving means, such as an adjusting magnet, if short opening times and a high actuation frequency are to be attained.
With this last apparatus as its point of departure, the object of the invention is to create a valve nozzle of the type referred to at the outset which is designed more favorably with respect to manufacture and the mass forces to be controlled.